1. Field of the Invention
The present invention relates to a device for compressing and molding a shredded tobacco or a filler stream before the filler stream is wrapped in wrapping paper in a cigarette manufacturing machine.
2. Description of the Related Art
In a cigarette manufacturing machine, a suction band sucks and attracts shredded tobacco into a form of layer so that a filler stream is formed on the suction band, and then travels the filler stream to one direction. The filler stream is peeled off from the suction band, and then is transferred onto wrapping paper, and thus passes through a compression-molding passage together with the wrapping paper. In a process of passing through the compression-molding passage, the filler stream is compressed and molded into a predetermined shape. Thereafter, the filler stream is wrapped in the wrapping paper, and then a tobacco rod is continuously formed. In the compression-molding passage, the compression-molding for the filler stream is significant in order to wrap the filler stream in the wrapping paper after that, that is, to stably formed the tobacco rod.
The formed tobacco rod is cut into individual cigarette rods having a predetermined length. The individual cigarette rods have a length twice as much as the cigarette portion of a filter-tipped cigarette. When the cigarette rod are supplied to a filter attachment, two filter-tipped cigarettes are manufactured from individual cigarette rods.
As shown in Japanese Utility Model Kokoku 62-33588 (27-8-1987), the aforementioned compression-molding passage is defined between a forming bed for guiding a travel of wrapping paper and a so-called tongue. The tongue has a shoe for peeling the filler stream from the suction band at its distal edge.
The tongue is a fixed member. Thus, in the case where the filler stream passes through the compression-molding passage, the tongue is a large resistance to the filler stream. For this reason, the shredded tobacco in the filler stream is easy to be broken by the tongue, and further the velocity of the filler stream fluctuates when passing through the compression-molding passage. The aforementioned breakage of the shredded tobacco and the velocity fluctuation of the filler stream are a factor of irregularly generating a hard spot and a soft spot relative to a filling density of the shredded tobacco in the filler stream. More specifically, the hard spot is a portion where the filling density is higher than a standard value; on the other hand, the soft spot is a portion where the filling density is lower than the standard value.
The hard spot in the filler stream causes filler stream jam in the compression-molding passage, and is a factor of causing a stoppage of the cigarette manufacturing machine. In the cigarette manufacturing machine, there is a tendency for the aforementioned filler stream jam to be frequently caused when forming a tobacco rod for a new brand cigarette or a different brand cigarettes.
On the other hand, when cutting the tobacco rod to obtain cigarette rod, there is the possibility that the soft spot in the filler stream exists in cut ends of the cigarette rod. In such a case, the shredded tobacco is easy to drop from the cut ends of the cigarette rod and a cut end of the filter-tipped cigarette.